Longwood
Longwood House in Longwood in June 1970
Longwood in Saint Helena
Sovereign state	United Kingdom
British overseas territory	Saint Helena, Ascension and Tristan da Cunha
Island	Saint Helena
Status	District
Area
• Total	33.4 km2 (12.9 sq mi)
Population  (2021)
• Total	765 (district)
• Density	21.4/km2 (55/sq mi)
Time zone	UTC+0 (GMT)

Longwood is a settlement and a district of the British island of Saint Helena in the South Atlantic Ocean.

Longwood had a population of 765 in 2021, a decrease of 195 residents when compared with the population of 960 recorded in 1998.^[1] The area of the district is 33.4 square kilometres (12.9 sq mi).^[2] The district is second only in size to Blue Hill, and includes the settlement of Hutt's Gate, with its St Matthew's church. The district also contains the island's only golf course.

The district contains Prosperous Bay Plain, which is where Saint Helena Airport and the Millennium Forest is located.

There is a weather recording station in the Longwood district. Readings of temperature, air pressure and visibility are automatically taken and communicated every three hours.^[3]

On leaving the University of Oxford, in 1676, Edmond Halley visited Saint Helena and set up an observatory with a 24-foot-long (7.3 m) aerial telescope with the intention of studying stars from the Southern Hemisphere.^[4] The site of this telescope is near St Matthew's church in the district. The 2,230-foot-high (680 m) hill there is named for him and is called Halley's Mount.

Halley's Observatory was in use from 1677–1678. Having returned to England in 1678, Halley published Catalogus Stellarum Australium in 1679, which included details of 341 southern stars. These additions to present-day star maps earned him comparison to Tycho Brahe. Halley was subsequently awarded his Master's from Oxford and Fellowship of the Royal Society.

In 1686, Halley published the second part of the results from his Helenian expedition, being a paper and chart on trade winds and monsoons. In this, he identified solar heating as the cause of atmospheric motions. He also established the relationship between barometric pressure and height above sea level. His charts were an important contribution to the emerging field of information visualisation.

Future Astronomer Nevil Maskelyne visited Saint Helena in 1761 to observe a transit of Venus and built an observatory near the site of Halley's from the previous century.^[5] In the 19th/early 20th centuries, an observatory (in use 1840–1849) was situated in Longwood village and two further observatories were erected in the Hutt's Gate area: one in use from 1892–1924 and the second in use from 1925–1975.

Longwood was the location of Napoleon's second exile, from 1815 until his death on 5 May 1821. France owns Briars Pavilion, Napoleon's initial exile residence, Longwood House and its properties, where he lived during most of his time on the island, and his original grave, but the United Kingdom retains ultimate sovereignty over these properties.

Napoleon's main physician, Barry O'Meara, wrote letters describing the issues of Napoleon and his entourage while in captivity, and sent them clandestinely to a friend at the Admiralty in London.^[6]

• 
  Landscape around Longwood House
• 
  The room in which Napoleon died
• 
  Longwood House in 1837
• 
  Night view of Napoleon's exhumation in October 1837

As opposed to the hot and arid Jamestown being near sea level, Longwood is located about 500 metres (1,600 ft) above sea level.^[7] Being one of the island's highest settlements, Longwood experiences a cooler variation of the warm-summer mediterranean climate (Köppen climate classification: Csb), bordering on a subtropical highland climate (Köppen climate classification: Cfb) due to its persistent mild temperatures and consistent precipitation levels. Due to its elevated geography, the town has abundant vegetation.^{[citation needed]}

• Longwood House

• Main habitations in St. Helena and their occupants^[usurped]

15°56′S 5°40′W / 15.933°S 5.667°W / -15.933; -5.667